Search and Seizure of Computer Data

Twenty years ago, computers were in the province of big businesses only. Computer data was a big mystery, coded in many different computer languages by proprietary software, uniquely tailored to the operations of a particular business or a single purpose, like billing, inventory, shipping, etc. It was not easily readable. Storage media was cumbersome and expensive (remember those huge hard disk platters and reel-to-reel tape drives?) and thus data was not stored indefinitely, and when it was, the media often had to be manually retrieved and mounted. So, even though computer data always contained much valuable information about a business, it was so time consuming and costly to extract that it was of little use or interest to anyone outside the business, including law enforcement.

Today, computers are prevalent everywhere, including homes and small offices. Programming languages have evolved, following conventional coding, and technology has developed making it possible to easily extract raw data and restore it to its useful original format. Storage media is cheap and plentiful. Stored data has exploded, stretching a vast array from proprietary secret formulas to home kitchen recipes.

Law enforcement agencies are very much aware of the potential of such information, and have forensic labs skilled in harvesting it. Balancing against this great potential use of information is the Fourth Amendment, which restricts police to “reasonable” searches and seizures. Except in emergencies, the Constitution presumes police will ordinarily obtain a warrant before conducting a search, and in such cases, searches are more likely to be viewed as “reasonable” by the courts. However, warrants require two important ingredients: “probable cause” and “particularity.” Probable cause is the quantity of evidence which must be presented to a magistrate demonstrating that a crime has been, or is about to be, committed, and that the evidence sought will be actually be found. It does not have to be overwhelming or convincing evidence, but must be more than mere suspicion. The “particularity” requirement compels the police to describe the premises and items sought with a high degree of specificity, and not simply go on a fishing expedition. Recently, the Massachusetts Supreme Judicial Court had the opportunity to review a search and seizure of a criminal defendant’s home computers. In Commonwealth v. McDermott, 448 Mass. 750 (2007), a widely reported case where the defendant shot and killed seven co-workers at his place of employment in Wakefield in December, 2000, police obtained a warrant for “documents reflecting the mental state and mental functioning of the defendant” in the days and weeks leading up to the shooting. The police seized five computers and computer disks, which they later had examined at a forensic lab, and recovered some 750 documents referencing the defendant’s behavior. The defendant challenged the search at trial, claiming (1) the police had insufficient probable cause to believe there were any relevant documents in his house or on his computers; (2) that the warrant failed the particularity requirement because no computers or disks were specified in the warrant; and (3) the method the police used to extract the data was too broad, exposing all sorts of data, even data beyond the “particular” data named in the warrant, to police scrutiny.

The Supreme Judicial Court sustained the search, making the following rulings:

(1) The Court found there was probable cause for the search because it was reasonably likely police would find documents confirming the defendant’s identity, weapon ownership, planning, motives, behavior, etc. Even though much of that information was already known and undisputed, the police still have the right to collect evidence confirming it.

(2) The Court found that the warrant seeking only “documents” was sufficiently particular to include computers and records on computers because they may “hide and store such records.” In essence, the Court found that the computers were merely “containers” of the documents sought, analogizing to established case law that permits the seizure of closed containers of contraband, such as guns or drugs in a closet or trunk. This came only after the Court described computers as simultaneously “file cabinets” storing millions of files, and “locked desk drawers” holding deeply private matter, but permitted the search anyway. In this regard, the Massachusetts court disregarded the analysis and holdings reached in other jurisdictions which have more zealously protected computer data as if it were privately locked away.

(3) The police had the right to remove the computers from the premises, even though they were not named in the warrant, to safeguard the data from deletion, and enable a more thorough search at a later time after a second warrant was obtained. In fact, the Court indicated the second warrant might be unnecessary if the later search is within the scope of the first warrant.

(4) Finally, the Court found that the method used by the police to examine the contents of the computer disks was sufficiently calculated to avoid a “fishing” expedition into private, unrelated documents. Police computer experts devised a search for 250 keywords, and used a hard disk recovery program which searched files for the occurrence of those keywords, opening the files in a special “preview” window where they could be viewed and printed without actually opening the files or making changes to the disk. The process identified 750 files which were printed and examined by police. This methodology clearly would not pass scrutiny under the guidelines established in other jurisdictions, nevertheless, the Massachusetts court was unconcerned and held that, under these circumstances, it was not a fishing expedition. The Court did not establish guidelines for any future searched. In fact, the Court said police experts were entitled to “considerable discretion” while weeding through the extraneous data, and were permitted to make a “cursory examination” of every file to determine its relevance.


The Massachusetts high court has been noted in the past for construing the Fourth Amendment more narrowly than other state and federal courts, providing greater protection to Massachusetts citizens against questionable search and seizure practices. Without a doubt, however, in the McDermott case, the SJC has placed the bar measurably lower. Clearly, police in Massachusetts now have broad latitude to sift through electronic data. In the future, Massachusetts businesses can expect search warrants of business records and computer data to be sustained if the documents and records sought are capable of being stored as computer data, and there is probable cause in the first place to obtain those records. Even if the documents and records obtained are not within the scope of the warrant, so long as the police make a reasonable effort to exclude obviously extraneous documents and records, what they do find is likely to be admissible in evidence as having been in “plain view” while they were legitimately searching for other records. And, even if the police don’t find what they are looking for, businesses can expect to be without their computers and data for long periods of time while the police conduct their forensic examination. With this relaxation of standards in criminal cases, one wonders whether the standards for discovery in civil cases will also bend.

Michael J. Tremblay

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